Hello @Bibek_Dhakal! I hope you are doing well. Say my Namaste to the beautiful Himalaya 
It’s great to hear that you are taking MLS. This post has great suggestions to read. Regarding your second query, how the course help in a career, there is no one answer. For me, it help me to gain the basics knowledge but was not enough to get a job. Then based on that learning, I did some advanced courses which helped to get a job.
Just for analogy, people get jobs based on a university degree, not on a high school degree, right? But without high school, one cannot get into the university. Same for this course which will give you the base to understand the high level.
Best,
Saif.